Single in/dual in mufflers.

[grahamsy2k]

I'm looking for people's opinion on whether dual in dual out mufflers preform better than single in dual out. Dual in dual out mufflers are hard to find.

I have a m20 and I'm just looking for a little different exhaust sound.

[Liquidity]

Need more info. If the inlets and outlets are all the same size, then it should be obvious that a dual/dual will flow more.

[grahamsy2k]

What is the size of factory muffler in a 325is m20, 2.5 in or 2.25 in?

My question isnt so much whether it will flow more because I understand that. It's whether the greater flow will noticeably change engine performance.

[G-Man the Visionary]

dual 1.75"?

[Liquidity]

What is the size of factory muffler in a 325is m20, 2.5 in or 2.25 in?

Inch? You think Germany uses English measuring standards?

[grahamsy2k]

Inch? You think Germany uses English measuring standards?

Thanks for your input...

[G-Man the Visionary]

Hahaha... I got the Borla dual in/ out pro xs for use with my m30. Like the sound, just too loud for me. Can't comment on performance gains since it's a swap. What part of Indiana are you from? I'm originally from Mishawaka/ South Bend.

[grahamsy2k]

Im in Terre haute. Hour southwest of Indy basically.

did some research and most people are saying that its 1.75''

[Madhatter]

44mm. So, yes, 1.75"

[digger]

dual 1.75" is same as about a single 2.5". as for mufflers it depends if it is a straight through type or something kind that might be more restrictive so the construction difference is important. chances are single 2.5" is plenty for what you need. i do like the sound of a dual system though